This invention relates to a dynamoelectric machine provided with slip rings and more particularly to an open type dynamoelectric machine mainly installed in the outdoors and provided with improved means for circulating cooling air through a chamber containing the slip rings.
In a dynamoelectric machine provided with a slip ring chamber such as a wound rotor induction motor, since the slip ring chamber and the housing of the motor are constructed such that air is independently admitted into and exhausted from the slip ring chamber and the motor housing, for the purpose of preventing foreign matter in the atmospheric air such as rain, snow and dust from entering the machine housing and the slip ring chamber, independent air circulating apparatus are provided for the slip ring chamber and the motor housing, respectively. As a result, the size of the slip ring chamber is increased and its construction becomes complicated.